This invention relates generally to dental anchors or pins used for retaining or reinforcing dental restorations, and, more particularly, to a dental anchor having buttress-type threads for the securement thereof in a tooth structure.
Dental anchors or pins for retaining or reinforcing dental restorations are well-known in the dental art, particularly dental anchors having threads thereon for securement in the tooth structure. Usually, such threaded dental anchors are self-threading and have been found to have the greatest retention capabilities when compared to other types of dental anchors or pins.
The most important aspect of using threaded dental anchors is to insure the proper amount of retention thereof, and at the same time to reduce the amount of dentin compression and to eliminate adverse effects upon the surrounding dentin. In the application of threaded dental anchors, it is essential that the practitioner avoid the generation of possible stress upon the dentition during the process of installing the threaded dental anchor into the tooth structure. Improperly inserted threaded dental anchors may result in crazing or cracking of the tooth structure, or at the least generate undesirable stresses on the existing dentin, especially at the blind end or bottom seat portion of the channel formed therefor in the tooth structure when the threaded dental anchor is fully inserted into the channel.
Buttress-type threads are well known in the screw art. However, the assignee of this application has recently discovered that buttress-type threads are extremely useful in the dental art for superb retention thereof in the tooth structure and also for rapid insertion thereof in the tooth structure causing minimal dentin displacement therein. The assignee's co-pending Ser. No. 06/517,006, now U.S. Pat. No. 4,767,332, discloses a dental anchor having a buttress-type thread thereon, where this buttress-type thread has the same structure as that used in the screw art, including a substantially planar upper surface facing away from the insertion end of the dental anchor, an angled or beveled lower surface tapering inwardly towards the insertion end of the dental anchor, and a flattened crest portion disposed between the planar upper surface and angled lower surface. This construction is what one skilled in the art normally assumes when refering to a buttress-type thread.
Though the above dental anchor structure having the buttress-type threads thereon has been proven quite useful in the dental art, the buttress-type thread structure of the present invention has been found to be superior thereto.